THERMODRAIN MODEL SELECTION

DRAIN WATER HEAT RECOVERY RESIDENTIAL MODEL SELECTION GUIDE

Always compare length versus efficiency. 

Your model selection is quite simple. Three different measurements will determine the model that is best suited for you. 

1. MEASURE THE DRAIN SIZE

ThermoDrain comes in 3″, 4″ or 6″ inner drain diameter. Begin by determining your drain size.

Measure and determine your drain diameter using this guide.

2. MEASURE THE LENGTH YOU CAN INSTALL

Measure the maximum vertical length where the ThermoDrain will be installed. Then subtract 2.5″ to allow for the installation of the drain couplings. For example: If you have 45″ of vertical pipe, you can install a 42.5″ long unit (45″-2.5″=42.5″).

Find the maximum length of drain water heat recovery for your application with this guide

3. FIND COLD WATER CONNECTION SIZE
NOTE: THERMODRAIN HAS A 3/4″ A FACTORY INSTALLED PEX OPTION 

Standard size is 3/4″. ThermoDrain is available from 1/2″ to 1.5″+

4. CALCULATE YOUR SAVINGS POTENTIAL

• Download our potential energy savings calculator to get a better idea what model works best for you
• DOWNLOAD CALCULATOR HERE

LOOKING FOR METRIC SIZES?

Note: We do offer the ThermoDrain in metric sizes. 110 and 75mm drain diameter x 22mm coil for countries that are currently using metric standard pipe sizes. The drain couplings supplied are also metric compatible.

LOOKING FOR A 2″ DRAIN DIAMETER?

Consider using a 3″ ThermoDrain on a 2″ drain stack if you have no other choice. Verify with local codes. Some areas will allow this due to the simple reason that no solids flow down a 2″ residential drain pipe. The Ontario Building Code 7.4.9.1 allows you to install a larger diameter ThermoDrain on a smaller diameter drain pipe and then return to a smaller diameter under these circumstances. 

ALWAYS LOOK AT THE EFFICIENCY OF THE UNIT VERSUS THE LENGTH!

• Always verify the efficiency versus length ratio. 
• What is the cost per % efficiency, never calculate cost per inch
• The higher the percent efficiency is per inch, the better the technology and the higher the value

TDH3320B-DR  =  Highest return on investment (compact performance)

• 32.0″ long
• 41.0% efficient
• 15.4 lbs
• 7.7 kW (25k BTU) heat recovery

TDH3320B-DR  =  42% (code required efficiency where specified)

• 32.0″ long
• 42.1% efficient
• 16.3 lbs
• 7.7 kW (27k BTU) heat recovery

TDH3620B-DR  =  NETZERO DESIGNED FOR HIGH PERFORMANCE HOMES

• 62.0″ long
• 57.2% efficient
• 32.4 lbs
• 10.7 kW (36.5k BTU) heat recovery